Ultrasound-assisted extraction of pumpkin seeds protein and its physicochemical and functional characterization

Abstract

Innovative utilization of the proteins in nutrition from wastes has been given great interest for promoting health-related food formulations. Pumpkin seeds are a rich source of nutritionally well-balanced proteins. This study deals with the effect of ultrasound power (100-300 W) and treatment time (10-20 min) on protein yield and protein recovery from defatted pumpkin seeds samples. The optimum conditions for extraction were 193.89 W and 19.08 min respectively, and the predicted value of protein recovery was 79.37 % and protein yield was 48.91%. The properties of the pumpkin seeds protein isolate (PSPI) were also analyzed and further compared with the pumpkin seeds sample. The protein content of the seeds sample and PSPI was found as 52.37 % and 86.07 % respectively. Bulk density, tapped density, water absorption capacity, fat absorption capacity, and compressibility index for defatted seeds sample and PSPI were 0.37 and 0.61 g/mL, 0.45 and 0.65 g/mL, 1.00 and 1.14 g/g, 0.90 and 1.20 g/g, 8.51 and 4.56 respectively. The maximum dispersibility was observed at pH 12 and the minimum at pH 9 for both the pumpkin seeds sample and PSPI. The onset temperature and melting point of PSPI was 48.8 °C and 84.3 °C respectively.

Keywords

• Pumpkin seeds
• protein yield
• protein recovery
• protein isolate